Responses of the Superficial Limb Veins of the Dog to Changes in Temperature

摘要: The lateral saphenous vein of the dog was perfused with homologous blood at constant, flow. Changes in perfusion pressure were used to measure active changes venous tone. Cooling perfusate caused constrict and warming relax. Most change occurred over temperature range 27° 42°C. powerful venoconstrictor response cooling depended on intact sympathetic nerves, since it reduced by lumbar sympathectomy largely abolished alpha-receptor or ganglionic blockade. confined being cooled. By comparison, body core when 37°C a generalized constriction superficial limb veins. These responses impaired anesthetic agents (for example, pentobarbital), hypoxia, arterial hypotension. data indicate role for cutaneous veins regulation. In cold, return is directed preferentially venae comitantes f...